羟基自由基杀灭压载水中有害赤潮物种的生物有效性研究

Research on biological effectiveness of hydroxyl radicals killing marine red tide algae in ballast water

本研究采用大气压下强电离放电协同气液混溶技术,高效制备羟基自由基（·OH）杀灭3个门的典型有害赤潮物种,使用荧光染色、测定光合作用潜能等生物学检测方法确定·OH致死阈值。结果表明,5.05×10^4 cells/mL的赤潮异弯藻（Heterosigma akashiwo）、5.28×10^4 cells/mL的亚历山大藻（Alexandrium tamarense）和5.02×10^4 cells/mL的中肋骨条藻（Skeletonema costatum）,其致死阈值分别为1.24mg/L、2.01mg/L、1.12mg/L,此时其叶绿素a分解率分别为77%、85%和74%。利用光学显微镜观察,处理前后藻细胞结构有明显的改变。因此,·OH致死方法可有效地杀灭压载水中的有害赤潮藻。

In this study, the three typical red tide species were chosen as the experiment algae and the inactivationwas achieved by hydroxyl radials generated from a strong ionization discharge combined with hydrodynamic cavita- tions. The viability and integrity of the algae were determined by the fluorescence staining and Pulse Amplitude Modulation. The results suggest that a quick and complete loss of viability was achieved for three species after ex- posure to hydroxyl radical,for the Heterosigma akashiwo ,Alexandrium tamarensem, Skelrtonema costatum which the density is 5.05 ×10^4 cells/mL,5.28×10^4 cells/mL,5.02 ×10^4 cells/mL respectively,the lethal thresholds are 1.24 mg/L,2.01mg/L,and 1.12 mg/L separately. Meanwhile Algal cells were deformed and shrunk after · OH attack and chlorophyll content was degraded at the same time. The chlorophyll content decomposition rate reaches to 77%, 85 % and 74 % at the lethal thresholds. Above all, the use of hydroxyl radicals is an efficient method to kill red tide species in ballast water.